Air-compressor



(No Model.)

M. S. MANNING, Jr.

AIR GOMPRESSOR. I

Patented'Apr. 11, 1882.

lNVENTUR WITNESSTS:

' UNITED STATES PATENT OFFICE.

MARK s. MANNING, JR, OF BROOKLYN, NEW YORK.

AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 256,232, dated April 11, 1882,

Application filed December 21, 1881. (No model.)

To all whom it may concern Be it known that I, MARK S. MANNING, Jr., of Brooklyn, Kings county, and State of New York, have invented a new and useful Improvement in Machines for Compressing Air, which is described in the followingspecification, with the accompanying drawings, in which- Figure 1 is a plan of my air-compressor, showing same connected with a steam-engine driving it. Fig. 2 is a longitudinal section. Fig. 3 is a transverse section on line 0, Fig. 2.

The object of my invention is to provide a free entrance of air into the compressing-cyL inder, to decrease the clearance-spaces at the end of the stroke, and to provide means by which the admission and emission of the air to and from the compressing-cylinder can be of its usual parts, is connected to the same crankshaft in the same way-via, by piston-rod Z, cross-head NV, and connecting-rod T.

M M are the air-compressor heads.

B is a circular valve-chest lined by the bushin gs E 'E,tightly secured to the casting. These bushings, being removable, can be removed when Worn by use. Their ends project beyond the face of the cylinder, in order to afford a bearing to the valve G, a recess being cut in the cylinder-heads to give them room. The open ends of the bushings serve as entranceports for the air into the valve-chest.

. G is a pistonvalve with three circular pistons, the two end pistons being fixed and the middle piston, H, being free and moving loosely on the stem.

D D are straight ports or passages between the compressing-cylinder and the valve-chest.

The operation of the machine is as follows: The piston-valve G is moved by any suitable mechanism-as the eccentric F or a cam. The rod' K of the eccentric or cam is attached directly to the piston-valve by the eye S, thus dispensing with the usual valve-rod. When the compressing-piston Pis near the beginning of its stroke, the piston-valve permits the entrance of air at the proper end of the cylinder A while air is being compressed at the other end; but it cannot escape until the pressure in the cylinder is a little greater than the pressure in the delivery-pipe O, the difference in the pressures being used to drive the loose piston H. \Vhen the piston P reaches the end of its stroke the valve G has moved into position for beginning another set of operations.

Itwill be seen that as the self-acting loose piston H is thrown from one side of the valvechest to the other it is prevented from striking a violent blow by the air inclosed between itself and the end of the valve toward which it is thrown; but when desirable spiral springs maybe used to ease the blow. One of the end pistons of the valve must be removable to enable the loose piston H to be placed in position, or the loose piston H may be made in halves for the same purpose.

The linings or bushings E E are secured tightly to the castings, and have suitable places cut out in order to keep the ports D D open, as shown in Figs. 2 and 3. While I prefer this mode of construction, they can, when desired, be cast in one piece with the valve-chest. The ports D D are made straight, and the valve-chest B is placed as closely as possible to the cylinder A. By these means the clearance or waste room at the end of the stroke is reduced to a minimum, and the machine is thereby enabled to be run at ordinary pressures without filling these spaces with water or other liquid.

By my above-described invention, in which I combine the use of a circular open-ended valvechest and compound piston, as described, for the admission and emission of the air into and from my air-compressing cylinder A, I gain several important advantages, of whichI enumerate the following:

a. The greatest possible access is permitted for the entrance of the air in consequence of the open ends of the cylindrical valve-chest acting as ports.

b. Friction is reduced and the amount of heat generated is greatly diminished.-

0. By the use of the open-ended valve-chest easy access to the valve is afforded for the purpose of examination and repair, and the removal and renewal of the valve is facilitated.

IOO

d. By the use of the straight ports D D, which have never before been used in an aircompressor, in combination with the above-(lescribed valve-chest, the 'clearan ce-spaces at the end of the stroke are diminished, while at the same time the construction of the appa atus is greatly simplified.

I am aware that in an invention for which Letters Patent No. 236,992 were granted to John R. (Jushier, dated January 25, 1881, a combination of two cylinders having each one open end and pistons of equal diameter working therein, with an intermediate close-ended cylinder of smaller dimensions and piston working therein, has been used. I11 this invention, however, theintermediate piston is fixed and does not slide, as shown in my invention; and, moreover, such cylinders and pistons are used as compressing-cylinders, and not, as in myinvention, asavalve-chest and piston-valve.

I do not claim the use of my open-ended circular valve-chest with the compound piston working therein, as described, for the purpose of a compressing-cylinder, nor for any other purpose than that described in this specification-namely, as a valve-chest for regulating the admission and emission of air to and from the compressing-cylinder A in an air-compressor, as before described.

Iani also aware that LettersP-atent No. 55,613 wereon the3dofApril,l866,granted to William Henderson for improvements in steam-engines, and that such invention shows a cylindrical valvechest with two piston-heads working therein, the said heads being united in motion and carrying between them a valve to which is imparted a stroke less than that of the drivingheads. Such invention, however, is only applicable to steam-engines, and could not be used for the same purposes as my open-ended val vechest. Thecylinder in the invention I'refer to is closed at the ends, whereas my cylinder is open at both ends.

I do not claim the use generally of a cylindrical valve-chest with three pistons working therein, nor do I claim the use thereot'in steamengines; but I desire to confine my claim to the use of such open-ended cylindrical valvechcst and compound piston working therein in air-compressors, for the purposes-before described.

Having thus described the nature of my invention, what I claim as new, and desire to protect by Letters Patent, is-

1. In an air-compressing machine, the combination of the piston-valve Gr, composed of three pistons, the center piston being self-acting and free to'move on its stem, with the circular valve-chest B open at both ends, such open ends acting as inlet-ports for the air to be compressed, substantially as described.

2. In an air-compressing machine, the combination of the piston-valve G, composed of two or more pistons, a circular valve-chest, B, open at both ends, the projecting linings E E, and the air-compressing cylinder A, connected with the valve-chest G by the ports D D, all substantially as shown and described, and operating in the manner and for the purposes herein set forth.

3. The linings E E of the circular open-ended valve-chest B, projecting beyond the face of the valve-chest and serving to give a suitable bearing to the valve G, substantially as described.

MARK S. MANNING, JR.

Witnesses:

Tnos. H. CORBETT, E. Weiss. 

